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<div class="sbspanel bottom" style="width:41%;"><img src="generated/latex-image/image-building-parabola.svg" role="img" class="contained" alt="a drawing of a tall building and a tennis ball being launched upward; the path of the ball is an arc that goes upward and then downward to the ground"></div>
<div class="sbspanel bottom" style="width:53%;"><img src="generated/latex-image/image-gaussian-sum-proof.svg" role="img" class="contained" alt="a visual proof of the identity that the sum of k from k = 1 to n is (n + 1) choose 2; there is a single ball at the top; beneath that there are two balls; beneath that there are three, then four, then five, then 6; this collection of balls represents the sum of k from k = 1 to 6; below all this are seven balls; the diagram illustrates a correspondence from any of the balls from the upper collection to a unique pair of two balls in the row of seven"></div>
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<figcaption><span class="type">Figure</span><span class="space"> </span><span class="codenumber">1.1.2<span class="period">.</span></span><span class="space"> </span><code class="code-inline tex2jax_ignore">tikz</code> Examples</figcaption></figure><span class="incontext"><a href="sec_1-intro.html#figure-1" class="internal">in-context</a></span>
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